The Water Cycle. The Water Cycle. The Water Cycle. Chapter 15 & 16 Water Resources. Properties of Water Supporting Life

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1 The Water Cycle Water Cycle: water molecules circulating between the Earth s surface and the atmosphere. Ted Talk Video Water Chapter 15 & 16 Water Resources It involves condensation evaporation transpiration precipitation 2 The Water Cycle The Water Cycle Condensation Evaporation Transpiration Precipitation Runoff Seepage Root Uptake Properties of Water Supporting Life High Specific Heat - fluctuations in heat are not as great as on land, reduce risk of temperature related problems Buoyancy- physical support allows for larger sized creatures with less rigid support Nutrient availability- nutrients are dissolved and on tap in surrounding waters Waste elimination- wastes are quickly dissolved, dispensed, and diluted 1

2 Global Water Distribution 71% of the Earth s surface is covered in water 97% of that water is salt water: Unusable 3% is freshwater: Usable by humans 77% of the fresh water is frozen in icecaps and glaciers Fresh water is a limited resource Potable Water: Drinkable Global Water Distribution Fresh Water Biomes Earth s surface water Streams, rivers, ponds, lakes and wetlands Total of fish species Lentic Waters: Still Lakes & Ponds Lotic Waters: Moving/flowing Streams, rivers Marshes, swamps, bogs Very productive ecosystems; Ecosystem services slowing: - runoff, reducing flooding, recharging groundwater, filtering pollutants Wetlands Over half have been drained and filled; many are now protected Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 2

3 How Wetlands Work Oligotrophic Low amounts of nutrients Ex: P and N Productivity in a lake High O 2 Mesotrophic Some organic matter. Low O 2 Eutrophic High levels of productivity Very Low O2 Mesotrophic Lakes & Ponds Littoral zone: - edge or shoreline Limnetic zone: - open water Profundal zone: - open water beyond sunlight s reach Benthic zone: - lake or pond bottom Aquifers: porous sediment that holds water (2 types) - Unconfined: porous rock covered by soil - Confined: surrounded by layer of impermeable rock or clay Recharge zone: An area in which water travels downward to become part of an aquifer. Percolation is the process of a liquid slowly passing through a filter. Pollution can enter Groundwater Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings 3

4 2/29/2016 Groundwater Water table: uppermost layer at which water in an area fully saturates the rock or soil Falls in dry weather Rises in wet weather Groundwater The Aquifer TheOgallala world s largest known aquifer Cone of depression- an area where there is no longer any groundwater; may cause sinkholes Zone of saturation is at a depth were ground is filled with water Great Plains of the U.S. 95% of water removed for irrigation (grains) Agriculture, municipal and industrial usage Removal rate is six times greater than the refreshing rate. Copyright 2008 Pearson Education, Inc., publishing as Pearson Benjamin Cummings Groundwater Major Aquifers of Georgia Aquifer Subsidence Groundwater-related subsidence is the subsidence (or the sinking) of land resulting from groundwater extraction. Area of Subsidence 1,2,3 Floridan aquifer 4. Claiborne, Clayton, Providence aquifers 5. Cretaceous Aquifer 4

5 Saltwater Intrusion The movement of saltwater into freshwater aquifers, which can lead to contamination of drinking water sources. Groundwater Porosity vs. Permeability Is the percentage of the total volume of a rock that has spaces or pores. The more porous a rock, the more water it can hold The ability of rock or soil to allow water to flow through it. Example: granite, sandstone, and limestone are permeable but clay is impermeable. Marine Biomes Consist of coastal ocean, open ocean, coral reefs, estuaries, coastal marshes, and mangrove swamps. 71% of earth's surface Currents distribute solar heat and regulate the earth's climate participate in nutrient cycles reservoir for carbon dioxide - thus help regulate temperature of the troposphere 2/3rds of population live within 100 miles of the ocean Ocean Terminology 1. Intertidal- land exposed to tides 2. Neretic- covers continental shelf (coral reefs) 3. Oceanic-less productive 4. Benthic- bottom floor 5. Abyss- deepest part of the ocean 6. Pelagic- Everything except areas near the coast 7. Photicphotosynthesis 8. Aphotic-no sunlight Ocean divided vertically 5

6 2/29/2016 Ocean water is vertically structured Oceans regulate the earth s climate They absorb and release heat Ocean s surface circulation Thermal Stratification Epilimnion- at the surface and warm water Thermocline-transition layer between the mixed layer at the surface and the deep water layer. Hypolimnion- deeper water and cold Ocean currents Surface winds and heating create vertical currents Upwelling = the vertical flow of cold, deep water towards the surface High primary productivity and lucrative fisheries Also occurs where strong winds blow away from, or parallel to, coastlines Simulation Ocean currents Currents = the upper waters of the ocean composed of vast riverlike flows Caused by winds and the movement of the earth The ocean currents move heat around the globe. Gulf Stream currents are rapid and powerful The warm water moderates El Nińo Europe s climate Open ocean systems Kelp forests Kelp = large, dense, brown algae growing from the floor of continental shelves Cold temperatures Shelter and food for organisms Absorbs wave energy and protects shorelines from erosion Used cosmetics, paints, paper, and soaps High Biodiversity 6

7 Open ocean systems Coral reefs Highest areas of biodiversity and most abundant of ocean organisms (plankton, nekton, and benthos) Protect shoreline by absorbing waves Found in the Neritic Zone in tropical waters Corals = tiny colonial marine organisms Coral reef = a mass of calcium carbonate composed of the skeletons of corals Open ocean systems Causes of decline of Coral reefs around the world 1. Coral bleaching = occurs when zooxanthellae leave the coral Coral lose their color and die, leaving white patches From climate change, pollution, or unknown natural causes 2. Nutrient pollution causes algal growth, which covers coral 3. Divers damage reefs by using cyanide to capture fish 4. Acidification of oceans deprives corals of necessary carbonate ions for their structural parts Intertidal zone Changing tides cause rocky shores to be completely covered with water at certain times and completely exposed to the air and sunlight at others. Salt marshes Salt marsh = occur along coasts at temperate latitude Tides wash over gently sloping, sandy, silty substrates High primary productivity Critical habitat for birds and commercial fish and shellfish species Filter pollution Stabilize shorelines against storm surges 7

8 Mangrove forests In tropical and subtropical latitudes coast lines Mangroves = trees with unique roots Curve upwards for oxygen Curve downwards for support Nurseries for commercial fish and shellfish Nesting areas for birds Food, medicine, tools, construction materials Estuaries Estuaries = water bodies where rivers flow into the ocean (freshwater mixes with saltwater) Wide fluctuations in salinity Critical habitat for shorebirds and shellfish Transitional zone (Fish spawn in freshwater, mature in salt water) Ex: Salmon Affected by development, pollution, habitat alteration, and overfishing Chesapeake Bay Largest estuary in the US. Very productive High amounts of pollution introduced Restoration program introduced in the 80s Human Impact on Coastal Zones Excess nutrients introduced to ocean due to runoff Can produce harmful algal blooms (red tide) The Gulf of Mexico s dead zone is currently the most notorious eutrophic body of water within the world. Hypoxia is a result of excess nutrients in the water, more specifically nitrates and phosphates. Wetlands destruction Toxic pollution Beach erosion Reduced resources Energy from the Ocean We extract energy from oceans Crude oil and Natural gas Oil spills damage fisheries Renewable energy sources, such as waves, tides, heat 8

9 Emptying the oceans We are placing unprecedented pressure on marine resources Half the world s marine fish populations are fully exploited Total fisheries catch leveled off after 1998, despite increased fishing effort It is predicted that populations of all ocean species we fish for today will collapse by the year 2048 Fishing has industrialized Factory fishing = highly industrialized, huge vessels use powerful technologies to capture fish in huge volumes Driftnets for schools of herring, sardines, mackerel, sharks Longline fishing for tuna and swordfish Trawling for pelagic fish and groundfish Seafood Watch Video Fishing has industrialized Fishing practices kill non-target animals We are fishing down the food chain As fishing increases, the size and age of fish caught decline 10-year-old cod, once common, are now rare By-catch = the accidental capture of animals Driftnetting drowns dolphins, turtles, and seals Longline fishing kills turtles, sharks, and albatrosses Bottom-trawling destroys communities Same level of destruction as clearcutting and strip mining As species become too rare to fish, fleets target other species 9

10 2/29/2016 We can protect areas in the ocean Marine protected areas (MPAs) = established along the coastlines of developed countries Protect habitat and habitat Support fisheries ( young fish are allowed to grow and replenish) Many commercial, recreation fishers, and businesses do not support marine reserves Altering the Availability of Water Levees- an enlarged bank built up on each side of the river. Dikes- similar to a levee but built to prevent ocean waters from flooding adjacent land. Altering the Availability of Water Dams- a barrier that runs across a river or stream to control the flow of water. World s Largest= Three Gorges. World's largest hydroelectric dam, Three Gorges, Yangtze River million people displaced 10

11 Altering the Availability of Water Dams Interruption of natural flow of water to which organisms are adapted. Fish ladders- a set of stairs with water flowing over them that have been added to some dams to help migrating fish such as salmon get upstream. Reservoir- the area where water is stored behind the dam. Dams Advantages Disadvantages No CO2 emissions Displaces people living behind or other ghgs dams Provides irrigation Decreases sediment/nutrient & drinking water flow downstream Provides flood Fish harvest downstream control decrease Cheap electricity Disrupts fish migration Reservoir can be patterns used for recreation Loss of water by evaporation such as boating Loss of some recreation such as fly-fishing, rafting 11